1. Field of the Invention
The present invention relates to a printer, such as a label printer, for conveying a label continuous body in which labels are temporarily adhered to a backing sheet and performing printing on the labels.
2. Description of the Related Art
In a label printer, a label continuous body (also referred to hereafter as a “sheet”) in which labels of a predetermined length are temporarily adhered to an elongated strip-form backing sheet (separator) at constant intervals is used as a printing medium, for example. The sheet is conveyed by a platen roller, and printing is performed on the labels using a heat generator of a thermal head provided on the opposite side of the sheet to the platen roller.
When the relative positions of the heat generator of the thermal head and the platen roller are different at this time, the printing quality deteriorates. Hence, the relative positions of the platen roller and the thermal head must be aligned accurately. Further, the thermal head is an expendable item, and therefore, the thermal head must be replaced when a part of the heat generator breaks down due to a disconnection or the like.
However, in a conventional label printer, a front-rear position of the thermal head (the front and rear of a parallel direction to a conveyance direction of the sheet) is adjusted by an operator by fixing the thermal head using left and right screws while viewing a printing sample, and therefore the adjustment operation takes time and leads to large irregularities and the like according to the operator. Moreover, to replace the thermal head, the left and right screws must be loosened, and therefore front-rear position adjustment must be performed again after the thermal head is replaced.
As related art, Japanese Unexamined Patent Application Publication 2003-48335 (Page 1, FIG. 1) discloses a head attachment/detachment mechanism in which an expendable thermal head can be attached and detached easily in a thermal printer in order to replace the head. In this head attachment/detachment mechanism, a rotatable attachment/detachment lever is disposed on a head substrate side, and by rotating the attachment/detachment lever, a part of a head support plate is pressed such that the head substrate side slips out from the head support plate side against the frictional resistance of a fitting portion between a connector on the head support plate side and a connector on the head substrate side. Thus, the thermal head can be attached and detached through a simple operation to rotate the attachment/detachment lever.
According to Japanese Unexamined Patent Application Publication 2003-48335, however, a head position adjustment mechanism must be provided separately to the head attachment/detachment mechanism to adjust the position of the head, and therefore the peripheral mechanisms of the head become complicated.